LDT-465 loss of power

[fpchief]

Hi,
I am trying to get another deuce up and running and i need some help with some initial troubleshooting. This is a Toole Army depot rebuild motor and it sounds like a new motor at idle, except for at the exhaust has a very slight what i would call a miss...there is no vapor of blow by that i can see. When on the road it has what i would call a loss of power compared to all deuces i have driven in the past and there is a miss sound coming from the motor. Is a good place to start on this looking for a bad or clogged injector? I do have some seepage around some injectors and on the HH. I am an decent back yard mechanic but have been lucky not to have any fuel delivery issues on any deuces i have had and think that is the problem on this one.







Very Respectfully,
Kip

 

[Floridianson]

Filters, pressures, boost then injectors all covered in the trouble shooting.https://www.steelsoldiers.com/showthread.php?116454-LDS465-1-Multifuel-Engine-Troubleshooting-Manual

 

[sandcobra164]

I would start with fixing the fuel leaks. On the hydraulic head you more than likely will have to remove the line just below in order to hang a wrench on the one that is leaking. I always start with the lower most line and work my way towards the block on both sides. Sounds counter productive but after a few wrench slips and skinned knuckles I consider it a time saver. The leak on top of the injector is on the return side and won't cause a misfire but could use some attention. I would certainly do as Floridianson and check / replace my fuel filters, verify the inlet pressure to ensure the in-tank pump is operational, clean / replace my air filter, etc. You may even find a goofball of a problem. I had a truck with low power once and the issue turned out to be a crushed hard line from the primary filter below the radiator. Proper testing pointed towards an obstructed primary filter below the alternator, looking around after replacing the filter found the true restriction. One other thing I would look at primarily would be valve lash adjustments. A valve that is "too tight" can cause a mis-fire as well. Lastly an exhaust gasket leak can "sound" like a mis-fire, look for soot around the exhaust ports to confirm / dismiss that thought. A few questions that will help members to point you in the right direction. How long have you had the truck? How often does it get driven? How is the condition of the fuel? What color is the fuel? I ask about the fuel so much because diesel tends to degrade much quicker these days. One thing I've learned with my trucks is they have to be run hard on a regular basis. I take mine for a 50 mile drive almost every week and one reason is to keep fresh diesel in the tank. If all of that checks out and you've fixed your fuel leaks, install a pyrometer and get ready to bump the go faster adjustment.

 

[fpchief]

Thanks for all of that. That was just what i was looking for. I just got this one and have zero history on it on how much driven, etc. I want to say due to the spider webs in between the duals, not much. I will just do as you said and start chipping away at possibilities. My '66 with what i think is its original motor will run loops around this one.

 

[fpchief]

Filters, pressures, boost then injectors all covered in the trouble shooting.https://www.steelsoldiers.com/showthread.php?116454-LDS465-1-Multifuel-Engine-Troubleshooting-Manual

Yessir!!! This truck came from not too far south of you too.

 

[Flyingvan911]

If you replace the fuel filters, be sure to replace all three at the same time.

 

[eric67camino]

Mine(52 mack m51a2) was having trouble maintaining over 40 mph, then started to cut out on takeoff. Found water in the system. Draining tanks and swapping filters should hopefully do the trick.

Not to hijack, but while changing the primary filter on mine yesterday, I noticed that the filter did not fit because the spring and washers were gone. Whether I lost them or the last guy did, I don't know. Does anyone know of a source for replacement or pn so I can get some?

 

[fpchief]

Mine(52 mack m51a2) was having trouble maintaining over 40 mph, then started to cut out on takeoff. Found water in the system. Draining tanks and swapping filters should hopefully do the trick.

Not to hijack, but while changing the primary filter on mine yesterday, I noticed that the filter did not fit because the spring and washers were gone. Whether I lost them or the last guy did, I don't know. Does anyone know of a source for replacement or pn so I can get some?

when i was looking for the same thing for my other truck, i believe i had to go to Eastern surplus for it.

 

[WillWagner]

Look at easy things first, make sure is getting full throttle.